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The Feasibility of Reintroducing White-Tailed Eagles Haliaeetus Albicilla to West Norfolk and Eastern England

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The Feasibility of Reintroducing White-Tailed Eagles Haliaeetus Albicilla to West Norfolk and Eastern England The feasibility of reintroducing White-tailed Eagles Haliaeetus albicilla to West Norfolk and eastern England Dr Tim Mackrill, Roy Dennis MBE, Dominic Buscall, Harry Buscall, Rod Pilcher, Nick Padwick, and Lloyd Park Version 2 April 2021 N.B. this version has been redacted for confidential information relating to funding and the specific location of White-tailed Eagles. 1 Contents List of Figures .......................................................................................................................................... 5 List of Tables ........................................................................................................................................... 6 Project team ............................................................................................................................................ 7 Executive Summary ............................................................................................................................... 10 1. Project goals and justification ....................................................................................................... 12 1.1. Aims and objectives .............................................................................................................. 12 1.2. The White-tailed Eagle .......................................................................................................... 13 1.3. History of the White-tailed Eagle in the UK .......................................................................... 15 1.4. Why should White-tailed Eagles be re-introduced to eastern England? .............................. 16 1.5. Why Ken Hill and West Norfolk? ........................................................................................... 21 1.6. Have the causes of extirpation been removed? ................................................................... 25 1.7. Have White-tailed Eagles been reintroduced elsewhere? ................................................... 28 1.8. What is the most appropriate donor stock? ......................................................................... 29 1.9. Impact on donor stock .......................................................................................................... 32 1.10. Legal requirements ........................................................................................................... 33 2. The biological feasibility of a White-tailed Eagle reintroduction.................................................. 36 2.1. Release site and the wider region ......................................................................................... 36 2.2. White-tailed Eagle diet ......................................................................................................... 38 2.3. Food availability .................................................................................................................... 50 2.3.1. Carrion ........................................................................................................................... 50 2.3.2. Fish ................................................................................................................................ 52 2.3.3. Waterbirds and other avian species ............................................................................. 54 2.3.4. Mammals ...................................................................................................................... 56 2.4. Breeding ................................................................................................................................ 60 2.4.1. Nesting habitat .............................................................................................................. 60 2.4.2. Nest site availability ...................................................................................................... 61 2.4.3. Monitoring of breeding sites ........................................................................................ 68 2.4.4. Conclusion ..................................................................................................................... 69 3. The ecological impact of a White-tailed Eagle reintroduction ..................................................... 71 3.1. Potential ecological impact ................................................................................................... 71 3.2. Spoonbills and rare egrets .................................................................................................... 73 2 3.3. Wintering bird assemblages ................................................................................................. 75 3.4. Breeding terns and gulls ....................................................................................................... 81 3.5. Lagomorphs .......................................................................................................................... 84 3.6. Potential predation of mesopredators ................................................................................. 85 3.7. Breeding waders ................................................................................................................... 88 3.8. Marine and freshwater fish .................................................................................................. 90 3.9. Common Cranes .................................................................................................................... 92 3.10. Beavers at Ken Hill ............................................................................................................ 93 3.11. Conclusion ......................................................................................................................... 93 4. The socioeconomic feasibility of a White-tailed Eagle reintroduction ......................................... 95 4.1. Potential socio-economic benefits........................................................................................ 95 4.2. Socioeconomic risks .............................................................................................................. 98 4.2.1. Sheep farming ............................................................................................................... 98 4.2.1.1. Sheep farming in Scotland ........................................................................................ 98 4.2.1.2. Sheep farming in Ireland, Netherlands and the Isle of Wight ................................ 100 4.2.1.3. Sheep farming in eastern England .......................................................................... 103 4.2.2. Pig Farming .................................................................................................................. 103 4.2.3. Poultry Farming ........................................................................................................... 107 4.2.4. Game shooting ............................................................................................................ 109 4.3.5. Fishing interests ............................................................................................................... 112 4.3.6. Forestry and Woodland Management .............................................................................. 115 4.3.7. Reporting Procedure ........................................................................................................ 116 4.3.8. Project team responsibilities during Phase 2 of the reintroduction ................................ 116 4.3.9. Conclusion ......................................................................................................................... 117 5. Stakeholder and public consultation .......................................................................................... 119 5.1. Introduction ........................................................................................................................ 119 5.2. Methodology ....................................................................................................................... 120 5.3. Results ................................................................................................................................. 123 5.3.1. Introduction ................................................................................................................ 123 5.3.2. Conservation ............................................................................................................... 123 5.3.3. Tourism ....................................................................................................................... 124 5.3.4. Game and Wildfowl .................................................................................................... 125 5.3.5. Farming ....................................................................................................................... 126 5.3.5.1. Arable farming ........................................................................................................ 127 3 5.3.5.2. Livestock farming .................................................................................................... 128 5.3.5.3. Poultry farming ....................................................................................................... 130 5.3.5.4. Fishing / fisheries .................................................................................................... 131 5.3.5.5. Private airfields and flying ......................................................................................
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